The Research Of Laser Beam Position Detection Technology In The Flatness Measurement System

In the shipbuilding process, the flatness of the hull is one of the important factors that affect the quality. When the process is completed, it is necessary to measure the flatness of the entire hull, in order to determine whether it complies with the requirements. Compared with traditional measurement methods, laser scanning measurement system has the characteristics of wide measurement range, high precision and fast detection. The laser spot position detection device is an important component of the system. It can ensure the accuracy of detection. In this paper, we design a set of spot position detection system by using the PSD.The system uses one-dimensional PSD as the laser spot detector. Comparing with other sensitive optoelectronic devices, it has the advantage of fast response, high resolution. And the output signal reflects the focus of beam. In this paper, we discuss the principle of spot detection. Based on this principle, we give the program of the detection system. The detection system consists of two parts, normalization processing and data acquisition. In the signal processing circuit, it completes the analog operation. The real-time focusing controller with the core of high-speed DSP chip TMS320VC5416 is designed. The AD chip with high resolution, high sampling rate ensure the collection of data. Through sorting algorithm, we determine the spot position. Finally, the results will be displayed in the LCD. According to the requirement of system, the necessary software system also has been provided.The preliminary experiment indicated that the system's technical approach is feasible, and establish the technology foundation for follow-up work.